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CHEM 210 Biochemistry Module 3
Exam (2024/2025) – Portage Learning
Questions and Verified Answers |
100% Guarantee Pass
Question 1
What is the primary structural feature of a fatty acid?
A. A glycerol backbone with three hydroxyl groups
B. A hydrocarbon chain with a carboxyl group
C. A phosphate group linked to glycerol
D. A sugar residue attached to a lipid
Correct Answer: B. A hydrocarbon chain with a carboxyl group
Rationale: Fatty acids are long hydrocarbon chains with a carboxyl group (-COOH) at one end,
which defines their amphipathic nature and role in lipid structures.
Question 2
Which type of fatty acid contains no double bonds in its hydrocarbon chain?
A. Unsaturated
B. Saturated
C. Polyunsaturated
D. Trans
Correct Answer: B. Saturated
Rationale: Saturated fatty acids lack double bonds, allowing tight packing of hydrocarbon
chains, resulting in higher melting points compared to unsaturated fatty acids.
Question 3
What is the primary function of triglycerides in the body?
A. Cell membrane formation
B. Energy storage
C. Signal transduction
D. Enzyme activation
, 2
Correct Answer: B. Energy storage
Rationale: Triglycerides, composed of glycerol and three fatty acids, serve as the body’s
primary energy storage molecules, stored in adipose tissue.
Question 4
Which component of a phospholipid is responsible for its hydrophilic properties?
A. Fatty acid tails
B. Glycerol backbone
C. Phosphate head group
D. Cholesterol
Correct Answer: C. Phosphate head group
Rationale: The phosphate head group in phospholipids is polar and hydrophilic, allowing
interaction with aqueous environments in cell membranes.
Question 5
What is the primary structural role of cholesterol in cell membranes?
A. Increases membrane fluidity
B. Stabilizes membrane structure
C. Forms ion channels
D. Acts as a signaling molecule
Correct Answer: B. Stabilizes membrane structure
Rationale: Cholesterol modulates membrane fluidity by stabilizing the lipid bilayer, preventing
excessive fluidity or rigidity, depending on temperature.
Question 6
Which fatty acid is an omega-3 fatty acid?
A. Palmitic acid
B. Oleic acid
C. Linolenic acid
D. Stearic acid
Correct Answer: C. Linolenic acid
Rationale: Linolenic acid is an omega-3 fatty acid with a double bond three carbons from the
methyl end, essential for health and not synthesized by the body.
Question 7
What type of bond links fatty acids to glycerol in triglycerides?
A. Glycosidic bond
B. Ester bond
CHEM 210 Biochemistry Module 3
Exam (2024/2025) – Portage Learning
Questions and Verified Answers |
100% Guarantee Pass
Question 1
What is the primary structural feature of a fatty acid?
A. A glycerol backbone with three hydroxyl groups
B. A hydrocarbon chain with a carboxyl group
C. A phosphate group linked to glycerol
D. A sugar residue attached to a lipid
Correct Answer: B. A hydrocarbon chain with a carboxyl group
Rationale: Fatty acids are long hydrocarbon chains with a carboxyl group (-COOH) at one end,
which defines their amphipathic nature and role in lipid structures.
Question 2
Which type of fatty acid contains no double bonds in its hydrocarbon chain?
A. Unsaturated
B. Saturated
C. Polyunsaturated
D. Trans
Correct Answer: B. Saturated
Rationale: Saturated fatty acids lack double bonds, allowing tight packing of hydrocarbon
chains, resulting in higher melting points compared to unsaturated fatty acids.
Question 3
What is the primary function of triglycerides in the body?
A. Cell membrane formation
B. Energy storage
C. Signal transduction
D. Enzyme activation
, 2
Correct Answer: B. Energy storage
Rationale: Triglycerides, composed of glycerol and three fatty acids, serve as the body’s
primary energy storage molecules, stored in adipose tissue.
Question 4
Which component of a phospholipid is responsible for its hydrophilic properties?
A. Fatty acid tails
B. Glycerol backbone
C. Phosphate head group
D. Cholesterol
Correct Answer: C. Phosphate head group
Rationale: The phosphate head group in phospholipids is polar and hydrophilic, allowing
interaction with aqueous environments in cell membranes.
Question 5
What is the primary structural role of cholesterol in cell membranes?
A. Increases membrane fluidity
B. Stabilizes membrane structure
C. Forms ion channels
D. Acts as a signaling molecule
Correct Answer: B. Stabilizes membrane structure
Rationale: Cholesterol modulates membrane fluidity by stabilizing the lipid bilayer, preventing
excessive fluidity or rigidity, depending on temperature.
Question 6
Which fatty acid is an omega-3 fatty acid?
A. Palmitic acid
B. Oleic acid
C. Linolenic acid
D. Stearic acid
Correct Answer: C. Linolenic acid
Rationale: Linolenic acid is an omega-3 fatty acid with a double bond three carbons from the
methyl end, essential for health and not synthesized by the body.
Question 7
What type of bond links fatty acids to glycerol in triglycerides?
A. Glycosidic bond
B. Ester bond
